Without a doubt the best accounts package for the Mac is Mondeydance. It's not the prettiest, but it is rock solid and does everything you could reasonably expect of an accounts package. The joy of it is that you can make it as simple or as complicated as you like and it is suitable for beginners right through to professional book-keepers. Unlike many personal accounts packages, the "categories" – to show income and expenditure under various headings – are not simply tags but fully-functioning accounts which allow proper journalling to keep even your accountant happy. Yet the beginner never sees this and doesn't need to know about it.
Moneydance will track all your bank accounts, credit cards, loans, mortgages, investments, assets and liabilities.
Now, for the first time, we have an iPhone app (it also works on the iPad, of course) which syncs with the desktop program. Up to now I've been entering raw data into Pocket Money on the iPhone – that is also a wonderful stand-alone app if that's what you need – but now have just one home for all my entries. For a V1 release, the Moneydance iPhone app (it's free, by the way) is outstanding. It's not intended as a full accounts package as, for instance, Pocket Money, but as an adjunct to the desktop package it is just right.
One of the big advantages of the desktop version of Moneydance is that there are versions for most platforms, including Mac, Windows and Linux. The data file is universal so you can save your data on a Mac and then open it on a Windows machine. I store my data file on Dropbox so the latest version is available wherever I'm working. A couple of years ago I had cause to thank Moneydance for this universality. My MacBook gave up the ghost while I was away from home. I desperately needed to access my accounts data (which I had on a backup disk) so I borrowed a PC, downloaded the app from the Moneydance site and was able to open and work on my file with no problems.
I can thoroughly recommend Moneydance for the Mac. It costs about £30, plus local taxes.